Prayer really works well on bosses. Use it and watch the boss try to attack the clone. Get behind the boss and unleash a combo but be quick the boss can knock down the clone before the 30 second that the close is supposed to be standing. At level 2 or 3 it starts to heal you and so if you are patient it's like having unlimited heal potions. You just have to wait for MP to regenerate before you use it again.

All of these are awesome. Ram is essentially a ranged attack and will run through an enemy that is far as long as you are locked on him. Quake is great al level 3 crushes any enemy in NG including those huge enemies holding big shields. Quake will hit them even if their shield is up and has AOE.